Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Wataru Fushimi

Shigeaki Suzuki

Yushi Naito

Yoshihiko Shirokura

Tadashi Yamaura

Shuji Ito

Yukimasa Sugino

Hisashi Yajima

Hideaki Ebisawa

Noriaki Kawano

Yuhshi Naito

A mobile wireless communication control device includes a moving object information holder that stores a communication state of each moving object which moves in a plurality of wireless zones and information showing a wireless zone to which the moving object belongs, and a call admission determinator that refers to the information held by the moving object information holder, and determines whether a moving object which is going to start communications can start the communications on the basis of the number of calls of moving objects in communication in a first wireless zone to which the moving object which is going to start the communications belongs, and the number of calls of moving objects in communication in a second wireless zone adjacent to the first wireless zone.

Mobile wireless communication control device and mobile wireless communication system

In a digital circuit multiplication equipment (DCME) equipped with tandem pass-through function, a speech coding device and a speech decoding device are resettable in a synchronous resetting mode. The DCME includes a transmission device and a unit to continuously assign and transmit data from a trunk channel to another DCME via a bearer circuit and an exchange during pass-through operation.

Digital circuit multiplication equipment

Digital circuit multiplication equipment (DCME) refers to coding bit rate information included in a pseudo-speech signal. In accordance with the coding bit rate information, the DCME selects either a coded speech signal extracted by a transmission bit rate restorer or a coded speech signal including bit rate identification information added by a coding bit rate information adding section, and supplies the selected coded speech signal to a bearer line. The DCME can solve a problem of a conventional DCME in that a mismatch can take place between the actual transmission bit rate of the coded speech signal and the transmission bit rate assigned to the bearer line when providing the variable bit rate DCME with a tandem passthrough function, and therefore the correct coding bit rate information cannot be transferred to a speech decoder, bringing about serious degradation in the speech quality.

Variable bit rate digital circuit multiplication equipment with tandem passthrough function

A voice transmitter includes a first selector for selecting an output of DTMF encoding means or that of voice-DTMF encoding means; DTMF transmission control means for monitoring each state, and for controlling selecting operation of the first selector; DTMF detecting means; and a second selector for selecting an output of voice encoding means or an output signal selected by the first selector by the DTMF detecting means.

Voice transmitter

In establishing an audio one link connection wherein an audio signal is not encoded/decoded in a relay station, loud noises may be produced if the states of two audio tandem relay devices which make a pair during relay are changed from a normal connection state to a relay connection state at different times. In order to solve this problem, comfort noise generators are provided. In detail, when a first pattern signal is detected while a relay call is connected via a relay exchange, switches are switched to be connected at a contact point,, and a switch is at a contact point,. Upon detection of a second pattern signal, the switches are connected at the contact points,, while the switches are connected at the contact points,. With this arrangement, outputs from the comfort noise generators are selected and outputted during a period from first pattern signal detection to second pattern signal detection, during which the states of the two devices of a pair are different. As a result, occurrence of loud noises is prevented.

Tandem relay device

When a signal is transmitted from an STM line to an ATM relay channel, the signal is compressed to be cell assembled into a cell. To the contrary, a signal from the ATM relay channel is cell disassembled into separate data and then expanded. In cases where signals are exchanged between ATM relay channels, a multistage relay device does not repeatedly execute signal compression/expansion to the signal. Switching for the above operations is achieved, utilizing a signal pattern inserted into audio data. With this arrangement, an audio one-link operation is established in the environment where an STM and an ATM coexist. Because compression/expansion processes are not repeatedly conducted, delay in relaying is avoided.

Multistage relay device

In a circuit multiplex transmission system for transmitting speech/facsimile signals, a transmission circuit allocation control unit outputs a data transmission rate designation signal according to the load of the transmission circuit. A facsimile procedure operating unit operates a facsimile procedure, by reloading a control signal to be used for controlling the facsimile procedure or by selectively causing a training, which takes place prior to sending a message, to end in failure, in such a manner that a facsimile base band data transmission rate will be a rate designated by a transmission rate designation information. The result is that since the facsimile base band data transmission rate is controlled according to the load of the transmission circuit, it is possible to accommodate the same number of input telephone lines as that if every input signal is a speech signal.

Circuit multiple transmission system

A signalling transmission system is disclosed which consists of a transmitting module including a signalling variation detecting unit and a signalling synthesization unit, and a receiving module including a signalling flag detecting unit and a signalling separation unit. The signalling synthesization unit makes composition signals by inserting signalling signals into voice signals together with a flag when signalling variations are detected by the variation detecting unit. A flag detecting unit detects a flag contained in the composition signals received by the receiving module and instructs the separating unit to separate the signalling signals from the voice signals contained the composition signals when the flag shows that the composition signals include the signalling signals. The signalling signals and the voice signals are therefore output from the receiving module.

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Tokyo, Japan

Wataru Fushimi